A first-person account of the DNF that ended a ten-race finish streak, the eighteen months it took to understand why, and the protein-first, muscle-protecting protocol built since — on the way to Kona, October 11, 2026.
Built at Ironman pace, for anyone on a GLP-1 who still wants the energy and power to perform — on race day, or on a normal Tuesday.
Twelve-plus years of full-distance finishes, two COVID cancellations, one DNF that forced a total rebuild, and a Legacy Program slot earned rather than qualified for.
I have finished ten Ironmans in a row before the day I didn't finish one. … I hadn't just lost twenty pounds. I'd lost muscle along with it, the kind of muscle an Ironman bike leg quietly depends on, and nobody had told me that was the trade I was making.
Rapid weight loss on a GLP-1 doesn't ask what kind of weight it's taking. For a sedentary body, that's the entire point. For an endurance athlete, it can quietly take the muscle a bike leg or a marathon depends on — and the scale won't tell you which one it took.
I found that out mid-race, at Ironman Brazil, after ten straight finishes. It took eighteen months to understand why. This is the system Christine and I have built since — still being tested, still being refined, on the way to Kona.
Read the full openingPrescribing information tells you the dose and the injection site. Nobody hands you the household manual for keeping your energy and power while the scale moves. These are the six adaptation problems the whole system is built to solve — whether your finish line is Kona or just getting through a normal week with something left in the tank.
Meals shrink or disappear. Protein drops before you notice. The fix is a floor, not a feeling.
Old meals feel too big. Restaurant choices get confusing. Small-meal frameworks replace guesswork.
The scale can say success while the engine underneath quietly loses horsepower. Ask us how we know.
Workouts feel flat when appetite is suppressed. Daily eating and workout fueling have to run as separate systems.
Restaurants, pizza night, a birthday dinner — portion tolerance changes, and nobody warns you it will.
No dosing advice here — just the practical kitchen, shopping, and training system we built because it didn't exist.
Real tools from the actual protocol — the same checklists and cards Stuart and Christine use every week to protect energy and power, not just to lose weight. Free to read, free to keep, more added as the book gets closer to done.
The exact 160–180g target, the food math behind it, and the order-of-operations rule that makes it hittable on a suppressed appetite.
Get the checklistCarbs, sodium, fluids, and recovery protein per hour — rebuilt after Brazil, race-tested at Jacksonville.
Get the cardThe one-hour weekly ritual — clean-out, plan, shop, prep — that runs the rest of our week on rails.
Get the one-pagerThe first few hundred words of Chapter One, exactly as they open the book.
I have finished ten Ironmans in a row before the day I didn't finish one.
Ironman Brazil. Rain most of the morning, a crosswind on the bike that everyone in the field was fighting, heat that came up hard once the sun found a gap in the clouds. Conditions, in other words — nothing a field of several thousand triathletes hadn't seen before, nothing I hadn't personally seen before. I've raced through worse.
What I hadn't seen before was this: I put in the same work I'd put into the ten races before it, followed a training program I could have written in my sleep by that point, and by the second half of the bike leg I understood, with a clarity that had nothing to do with panic, that the day was not going to end the way the last ten had…
A first-person story of the Ironman Brazil DNF that ended a ten-race finish streak, the eighteen months it took to understand why, and the protein-first, muscle-protecting system built since — paired with a practical guide for any athlete navigating the same intersection.
A second book, giving more space to the people who lived this alongside him, may follow — with their own say in what that looks like.
Be first to know when it's outStuart Nixdorff is an 18x Ironman finisher, entrepreneur, and author, currently training for the IRONMAN World Championship in Kona (October 11, 2026) via the IRONMAN Legacy Program — earned through more than a decade of full-distance finishes rather than a competitive qualifying slot.
He and his wife Christine are both active GLP-1 users. This project — the book, the practical system, and this site — is the record of what they've built since a DNF at Ironman Brazil forced a hard rethink of what “successful weight loss” actually means for a working endurance athlete.
No. This site and the book describe one person's lifestyle system and personal experience. Nothing here is dosing guidance, and nothing replaces a conversation with your own prescribing clinician or a registered dietitian. Always talk to your doctor before changing your medication, training, or nutrition.
No. Ozempic® is a registered trademark of Novo Nordisk A/S. This is an independent project describing personal experience with GLP-1 medications generally. It is not sponsored by, affiliated with, or endorsed by Novo Nordisk.
No. WADA added semaglutide and tirzepatide to its Monitoring Program — tracked for data purposes, not prohibited. There's no sanction for using one today. WADA has signaled a possible prohibition decision by late 2026 or 2027; we're tracking it and will update this page the day that changes. Stuart competes in the age-group/Legacy field, not as a professional or in the elite pool subject to out-of-competition testing, and will follow whatever rules apply to him as they're issued.
Regulatory status as of July 2026 — last checked July 7, 2026.
A full first draft exists and is in active editing. We haven't set a publication date — part of the point of this book is being honest about Kona (October 11, 2026) before it happens, not after. Join the list below for real updates, not a countdown timer we don't believe.
No. The system is built from Ironman training, but the core problems — appetite loss, muscle preservation, fueling on a schedule instead of a signal — apply to anyone on a GLP-1 who wants to keep their energy and power, not just watch the scale move. That's weekend runners and strength athletes, but it's also anyone busy enough that "what's for dinner" keeps losing to the day.
No drip campaign, no upsell funnel — just an email when there's something real to read, starting with early chapters for people navigating this themselves.
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